// Copyright 2005, Google Inc.
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//
//     * Redistributions of source code must retain the above copyright
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// in the documentation and/or other materials provided with the
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//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: wan@google.com (Zhanyong Wan), eefacm@gmail.com (Sean Mcafee)
//
// The Google C++ Testing Framework (Google Test)
//
// This header file defines internal utilities needed for implementing
// death tests.  They are subject to change without notice.

#ifndef GTEST_INCLUDE_GTEST_INTERNAL_GTEST_DEATH_TEST_INTERNAL_H_
#define GTEST_INCLUDE_GTEST_INTERNAL_GTEST_DEATH_TEST_INTERNAL_H_

#include "gtest/internal/gtest-internal.h"

#include <stdio.h>

namespace testing
{
	namespace internal
	{

		GTEST_DECLARE_string_(internal_run_death_test);

		// Names of the flags (needed for parsing Google Test flags).
		const char kDeathTestStyleFlag[] = "death_test_style";
		const char kDeathTestUseFork[] = "death_test_use_fork";
		const char kInternalRunDeathTestFlag[] = "internal_run_death_test";

#if GTEST_HAS_DEATH_TEST

		// DeathTest is a class that hides much of the complexity of the
		// GTEST_DEATH_TEST_ macro.  It is abstract; its static Create method
		// returns a concrete class that depends on the prevailing death test
		// style, as defined by the --gtest_death_test_style and/or
		// --gtest_internal_run_death_test flags.

		// In describing the results of death tests, these terms are used with
		// the corresponding definitions:
		//
		// exit status:  The integer exit information in the format specified
		//               by wait(2)
		// exit code:    The integer code passed to exit(3), _exit(2), or
		//               returned from main()
		class GTEST_API_ DeathTest
		{
		public:
			// Create returns false if there was an error determining the
			// appropriate action to take for the current death test; for example,
			// if the gtest_death_test_style flag is set to an invalid value.
			// The LastMessage method will return a more detailed message in that
			// case.  Otherwise, the DeathTest pointer pointed to by the "test"
			// argument is set.  If the death test should be skipped, the pointer
			// is set to NULL; otherwise, it is set to the address of a new concrete
			// DeathTest object that controls the execution of the current test.
			static bool Create(const char *statement, const RE *regex,
			                   const char *file, int line, DeathTest **test);
			DeathTest();
			virtual ~DeathTest() { }

			// A helper class that aborts a death test when it's deleted.
			class ReturnSentinel
			{
			public:
				explicit ReturnSentinel(DeathTest *test) : test_(test) { }
				~ReturnSentinel()
				{
					test_->Abort(TEST_ENCOUNTERED_RETURN_STATEMENT);
				}
			private:
				DeathTest *const test_;
				GTEST_DISALLOW_COPY_AND_ASSIGN_(ReturnSentinel);
			} GTEST_ATTRIBUTE_UNUSED_;

			// An enumeration of possible roles that may be taken when a death
			// test is encountered.  EXECUTE means that the death test logic should
			// be executed immediately.  OVERSEE means that the program should prepare
			// the appropriate environment for a child process to execute the death
			// test, then wait for it to complete.
			enum TestRole { OVERSEE_TEST, EXECUTE_TEST };

			// An enumeration of the three reasons that a test might be aborted.
			enum AbortReason
			{
				TEST_ENCOUNTERED_RETURN_STATEMENT,
				TEST_THREW_EXCEPTION,
				TEST_DID_NOT_DIE
			};

			// Assumes one of the above roles.
			virtual TestRole AssumeRole() = 0;

			// Waits for the death test to finish and returns its status.
			virtual int Wait() = 0;

			// Returns true if the death test passed; that is, the test process
			// exited during the test, its exit status matches a user-supplied
			// predicate, and its stderr output matches a user-supplied regular
			// expression.
			// The user-supplied predicate may be a macro expression rather
			// than a function pointer or functor, or else Wait and Passed could
			// be combined.
			virtual bool Passed(bool exit_status_ok) = 0;

			// Signals that the death test did not die as expected.
			virtual void Abort(AbortReason reason) = 0;

			// Returns a human-readable outcome message regarding the outcome of
			// the last death test.
			static const char *LastMessage();

			static void set_last_death_test_message(const std::string &message);

		private:
			// A string containing a description of the outcome of the last death test.
			static std::string last_death_test_message_;

			GTEST_DISALLOW_COPY_AND_ASSIGN_(DeathTest);
		};

		// Factory interface for death tests.  May be mocked out for testing.
		class DeathTestFactory
		{
		public:
			virtual ~DeathTestFactory() { }
			virtual bool Create(const char *statement, const RE *regex,
			                    const char *file, int line, DeathTest **test) = 0;
		};

		// A concrete DeathTestFactory implementation for normal use.
		class DefaultDeathTestFactory : public DeathTestFactory
		{
		public:
			virtual bool Create(const char *statement, const RE *regex,
			                    const char *file, int line, DeathTest **test);
		};

		// Returns true if exit_status describes a process that was terminated
		// by a signal, or exited normally with a nonzero exit code.
		GTEST_API_ bool ExitedUnsuccessfully(int exit_status);

		// Traps C++ exceptions escaping statement and reports them as test
		// failures. Note that trapping SEH exceptions is not implemented here.
# if GTEST_HAS_EXCEPTIONS
#  define GTEST_EXECUTE_DEATH_TEST_STATEMENT_(statement, death_test) \
	try { \
		GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement); \
	} catch (const ::std::exception& gtest_exception) { \
		fprintf(\
		        stderr, \
		        "\n%s: Caught std::exception-derived exception escaping the " \
		        "death test statement. Exception message: %s\n", \
		        ::testing::internal::FormatFileLocation(__FILE__, __LINE__).c_str(), \
		        gtest_exception.what()); \
		fflush(stderr); \
		death_test->Abort(::testing::internal::DeathTest::TEST_THREW_EXCEPTION); \
	} catch (...) { \
		death_test->Abort(::testing::internal::DeathTest::TEST_THREW_EXCEPTION); \
	}

# else
#  define GTEST_EXECUTE_DEATH_TEST_STATEMENT_(statement, death_test) \
	GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement)

# endif

		// This macro is for implementing ASSERT_DEATH*, EXPECT_DEATH*,
		// ASSERT_EXIT*, and EXPECT_EXIT*.
# define GTEST_DEATH_TEST_(statement, predicate, regex, fail) \
	GTEST_AMBIGUOUS_ELSE_BLOCKER_ \
	if (::testing::internal::AlwaysTrue()) { \
		const ::testing::internal::RE& gtest_regex = (regex); \
		::testing::internal::DeathTest* gtest_dt; \
		if (!::testing::internal::DeathTest::Create(#statement, &gtest_regex, \
		                                            __FILE__, __LINE__, &gtest_dt)) { \
			goto GTEST_CONCAT_TOKEN_(gtest_label_, __LINE__); \
		} \
		if (gtest_dt != NULL) { \
			::testing::internal::scoped_ptr< ::testing::internal::DeathTest> \
			gtest_dt_ptr(gtest_dt); \
			switch (gtest_dt->AssumeRole()) { \
			case ::testing::internal::DeathTest::OVERSEE_TEST: \
				if (!gtest_dt->Passed(predicate(gtest_dt->Wait()))) { \
					goto GTEST_CONCAT_TOKEN_(gtest_label_, __LINE__); \
				} \
				break; \
			case ::testing::internal::DeathTest::EXECUTE_TEST: { \
					::testing::internal::DeathTest::ReturnSentinel \
					gtest_sentinel(gtest_dt); \
					GTEST_EXECUTE_DEATH_TEST_STATEMENT_(statement, gtest_dt); \
					gtest_dt->Abort(::testing::internal::DeathTest::TEST_DID_NOT_DIE); \
					break; \
				} \
			default: \
				break; \
			} \
		} \
	} else \
		GTEST_CONCAT_TOKEN_(gtest_label_, __LINE__): \
			fail(::testing::internal::DeathTest::LastMessage())
		// The symbol "fail" here expands to something into which a message
		// can be streamed.

		// This macro is for implementing ASSERT/EXPECT_DEBUG_DEATH when compiled in
		// NDEBUG mode. In this case we need the statements to be executed, the regex is
		// ignored, and the macro must accept a streamed message even though the message
		// is never printed.
# define GTEST_EXECUTE_STATEMENT_(statement, regex) \
	GTEST_AMBIGUOUS_ELSE_BLOCKER_ \
	if (::testing::internal::AlwaysTrue()) { \
		GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement); \
	} else \
		::testing::Message()

		// A class representing the parsed contents of the
		// --gtest_internal_run_death_test flag, as it existed when
		// RUN_ALL_TESTS was called.
		class InternalRunDeathTestFlag
		{
		public:
			InternalRunDeathTestFlag(const std::string &a_file,
			                         int a_line,
			                         int an_index,
			                         int a_write_fd)
				: file_(a_file), line_(a_line), index_(an_index),
				  write_fd_(a_write_fd) {}

			~InternalRunDeathTestFlag()
			{
				if (write_fd_ >= 0)
					posix::Close(write_fd_);
			}

			const std::string &file() const
			{
				return file_;
			}
			int line() const
			{
				return line_;
			}
			int index() const
			{
				return index_;
			}
			int write_fd() const
			{
				return write_fd_;
			}

		private:
			std::string file_;
			int line_;
			int index_;
			int write_fd_;

			GTEST_DISALLOW_COPY_AND_ASSIGN_(InternalRunDeathTestFlag);
		};

		// Returns a newly created InternalRunDeathTestFlag object with fields
		// initialized from the GTEST_FLAG(internal_run_death_test) flag if
		// the flag is specified; otherwise returns NULL.
		InternalRunDeathTestFlag *ParseInternalRunDeathTestFlag();

#else  // GTEST_HAS_DEATH_TEST

		// This macro is used for implementing macros such as
		// EXPECT_DEATH_IF_SUPPORTED and ASSERT_DEATH_IF_SUPPORTED on systems where
		// death tests are not supported. Those macros must compile on such systems
		// iff EXPECT_DEATH and ASSERT_DEATH compile with the same parameters on
		// systems that support death tests. This allows one to write such a macro
		// on a system that does not support death tests and be sure that it will
		// compile on a death-test supporting system.
		//
		// Parameters:
		//   statement -  A statement that a macro such as EXPECT_DEATH would test
		//                for program termination. This macro has to make sure this
		//                statement is compiled but not executed, to ensure that
		//                EXPECT_DEATH_IF_SUPPORTED compiles with a certain
		//                parameter iff EXPECT_DEATH compiles with it.
		//   regex     -  A regex that a macro such as EXPECT_DEATH would use to test
		//                the output of statement.  This parameter has to be
		//                compiled but not evaluated by this macro, to ensure that
		//                this macro only accepts expressions that a macro such as
		//                EXPECT_DEATH would accept.
		//   terminator - Must be an empty statement for EXPECT_DEATH_IF_SUPPORTED
		//                and a return statement for ASSERT_DEATH_IF_SUPPORTED.
		//                This ensures that ASSERT_DEATH_IF_SUPPORTED will not
		//                compile inside functions where ASSERT_DEATH doesn't
		//                compile.
		//
		//  The branch that has an always false condition is used to ensure that
		//  statement and regex are compiled (and thus syntactically correct) but
		//  never executed. The unreachable code macro protects the terminator
		//  statement from generating an 'unreachable code' warning in case
		//  statement unconditionally returns or throws. The Message constructor at
		//  the end allows the syntax of streaming additional messages into the
		//  macro, for compilational compatibility with EXPECT_DEATH/ASSERT_DEATH.
# define GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, terminator) \
	GTEST_AMBIGUOUS_ELSE_BLOCKER_ \
	if (::testing::internal::AlwaysTrue()) { \
		GTEST_LOG_(WARNING) \
		        << "Death tests are not supported on this platform.\n" \
		        << "Statement '" #statement "' cannot be verified."; \
	} else if (::testing::internal::AlwaysFalse()) { \
		::testing::internal::RE::PartialMatch(".*", (regex)); \
		GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement); \
		terminator; \
	} else \
		::testing::Message()

#endif  // GTEST_HAS_DEATH_TEST

	}  // namespace internal
}  // namespace testing

#endif  // GTEST_INCLUDE_GTEST_INTERNAL_GTEST_DEATH_TEST_INTERNAL_H_
